A Geometric church by William Slater 1857-65. Aisled nave, buttressed NE vestry, NW steeple, narthex and octagonal baptistry. The lean-to roofs of the buttressed aisles reach nearly to the nave eaves, so there is no clerestory. The stark tower is of two huge stages, the first with a statue of St Peter by Dorothy M. McKay, 1935, over the tall entrance arch, the second with lancet openings to the belfry. The spire, 56 m. high, is diapered with bands of ornament and cinquefoils.
A lofty porch in the tower is followed by the flat-roofed narthex like a cloister opening west into the vaulted baptistry, east into the church. The broad five-bay nave arcade is on polished Peterhead granite piers. The aisles continue a further bay to flank the choir but have their own ‘chancel arches’ The organ chamber is situated in the east bay of the south aisle.
The stencilled decoration of the braced collar-beamed nave and aisle roofs is by G H Potts; the chancel roof is painted with sacred symbols, the wall with panels of the evangelists and the Agnus Dei both by George Dobie & son in 1890.
Expensive furnishings of 1865: round Caen stone pulpit on marble shafts by Poole; choir stalls carved by Forsythe; elaborate scheme of encaustic tiles in the chancel by Minton; stained glass (chancel windows by Clayton & Bell 1865); in the east bay of the north aisle the Duncan memorial window by Isobel Goudie 1935; the next two windows of this aisle and the three east windows of the south aisle by Clayton & Bell c. 1865-80; the Baxendine memorial window after 1918 and the Dawson and Robertson window c.1930; in the baptistry one light (Blessed are the Pure in Heart) after 1898.
The organ is by Frederick Holt 1865, rebuilt by Schovell in 1913 and by Rushforth & Dreaper in 1959-60 with subsequent additions in 1986 and 1997.
 Now a memorial chapel to the Rev. B E R Millar, Rector 1954-71
 Now hidden by carpeting