This one-man show is something of a minor masterpiece, combining a carefully crafted script, an exceptional performance and, most importantly, real affection for its subject matter.

Humphrey Ker - one third of the Penny Dreadfuls, here making his Fringe solo debut - recounts the story of one Dymock Watson, reluctantly drafted into World War II naval intelligence to smash a Nazi plot to construct the first atomic bomb. The fact that the character is loosely based on Ker's grandfather only adds to the poignancy: yes, it's a comedy show, and the laughs come thick and fast, but there's a great respect for the older man's bravery that moves the show past sarcastic parody into something far subtler and more celebratory.

Ker summons a huge array of eccentric characters for his endlessly inventive show, and he brings them all to vivid life with deft and effortless characterisation. There's a seductive New Orleans vamp, an aggressive Geordie sergeant and, most memorably, a Nazi stand-up comic with truly appalling material.

Ker's script is densely packed with jokes and delivered with engaging energy. He casts knowing glances at the audience, comments on his own material, and there's even superb physical comedy. It's a slick and stylish show that also manages to be generous and warm-hearted.

- David Kettle