Arthur & George (ITV, 9pm)

SHE'S due to be seen in a fictional TV adventure with an elderly Sherlock Holmes, played by Sir Ian McKellen, in Mr Holmes, so there's a detecting connection for Hattie Morahan at the moment as millions watch her as the real life Jean Leckie, Sir Arthur Conan Doyle's love interest in three-part series Arthur & George.

Morahan admires her character’s patience and fortitude for waiting so long for Sir Arthur Conan Doyle (Martin Clunes) to propose marriage.

“I think it must have been very difficult at the time to contend with other people’s gossip and sense of scandal. They had to endure that quite a lot; people making assumptions about the relationship. We still don’t know whether they were utterly platonic before his wife died. To give them the benefit of the doubt, it seems that is what they tried to do. I think there was an awful lot of gossip. When they got married there was a lot of sneering about their relationship. The good thing is that they remained together until he died, and they had children. It was obviously an absolute meeting of souls," says Morahan.

Would the actress have waited that long? “If this is the person you love more than anything else in the world, then what can you do. It is going to make you more miserable walking away from the relationship. There is a moment in the story where we see her reaching the end of her tether, and saying ‘It’s been great, I don’t regret a moment, but I can’t do this any longer’. Her taking that step makes him reconsider his position."

Morahan, who is the daughter of Anna Cartaret and Jewel in the Crown director Christopher Morahan, is best-known for starring in TV drama The Bletchley Circle, playing Jane in the TV comedy Outnumbered and lovelorn Elinor Dashwood in a BBC adaptation of Sense and Sensibility.

She has also recently filmed The Outcast, for BBC, an adaptation of the Sadie Jones novel and the feature film Alice Through the Looking Glass.

Tonight, Arthur, Woodie and the Edaljis are surprised by George (Arsher Ali) turning up at the Vicarage: George. This leads Woodie to further question whether it was in fact, George, who was the Wyrley Ripper after all.

Arthur is then given evidence that George is consorting with known criminals.

More Tales from Northumberland with Robson Green (ITV, 8pm)

ROBSON Green goes off on the trail of some of Northumberland’s greatest historical treasures.

He heads to the Farne Islands to go diving for shipwrecks, and discovers some mysterious cannons and the wreck of a ship sunk by the German Luftwaffe in 1941.

Green also finds out about the fascinating Roman relics that have been unearthed in the region, like the Corbridge Hoard, discovered by students in the 1960s, and the Vindolanda Tablets - the oldest handwritten documents in Britain.

Finally he visits the Holy Island of Lindisfarne to learn about the Viking invasion of the island and hears about the legacy left behind by the Norse invaders.

Waterloo Road (BBC1, 11.15pm)

AS the series wraps up, the school pulls out all the stops in a desperate bid to halt the merger with Havelock High, and with no Vaughan (Neil Pearson), the students take matters into their own hands and try to uncover the council's real plans, after discovering it's been less than transparent before now. But with the council and its supporters out in force to convince the community and parents that the merger is the best outcome for everyone, who will win?

Meanwhile, Marco (Stefano Braschi) has suspicions about Lorna's (Laura Aikman) ex-husband. However, Marcco's meddling only serves to land him and Kenzie (Charlotte Beaumont) in a dangerous situation.

Speaking of Kenzie, she has a decision to make - who will finally win her heart, Scott (Andrew Still) or Justin (Max Bowden)?

Laurie Brett also stars.