Penhill struck for the second year running at the Cheltenham Festival when springing a 12-1 surprise for trainer Willie Mullins in the Stayers' Hurdle.
Successful in the Albert Bartlett in 2017, Penhill had been absent for 323 days but shrugged off his race-rustiness to give Mullins his sixth winner of the week.
Ridden by Paul Townend, Penhill carried the colours of Brighton chairman Tony Bloom home by two lengths from Supasundae, following a scrap up the hill.
Wholestone stayed on strongly for third.
Townend said: "He's got a massive engine.
"It was some training performance. I got there too soon and luckily he kept going
"He jumped rusty enough early on but when I needed him at the last he produced."
Mullins said: "It's fantastic for connections. I want to put him away now for Cheltenham next year.
"He's not suited to training to the Flat and he's able to do this job so well."